Silencer



Aug. 31, 1948. w, MASON 2,448,382

SILENCER Filed 001;. 26, 1944 INVENTOR By WP MASON ATTORNEY PatentedAug. 31, 1948 UNITED STATES PATENT OFFICE Warren E. Mason, Vest Orange,N. J., assignor to Bell Telephone Laboratories, Incorporated, New York,N. Y., a corporation of New York Application October 26, 1944, SerialNo. 560,456

2 Claims. I

This invention relates to firearms and more particularly to a silencerfor reducing the muzzle blast.

The principal object of the invention is to reduce the noise associatedwith the muzzle blast of a firearm. Other objects are to reduce theweight, size and cost of a silencer and improve the stability ofperformance.

Important factors in silencing the muzzle blast of a firearm are therapid cooling of the power gases and the reduction of pressure beforethey emerge. An effective silencer utilizing these principles comprisesa chamber containing heat absorbing material through which the bulletpasses. The effectiveness of such a device depends, among other things,upon its cross-sec tional area. Applicant has discovered, however, thatthe importance of having a large crosssectional area diminishesconsiderably toward the front end of the silencer.

In accordance with the invention, therefore, the chamber has at itsfront end a section of reduced cross-sectional area. Weight, size andcost are reduced without seriously affecting the efiiciency of noisereduction. The silencer may be built as an attachment or, preferably,the rear portion of the chamber may be built around the barrel of thefirearm, with communicating holes through the barrel. The heat absorbingmaterial may be metal screen, which may take the form of apertureddiscs, stacked one upon another and preferably held in compression.Plating the screen with some metal such as tin before punching the discswill increase the stability of performance.

The nature of the invention will be more fully understood from thefollowing detailed description and by reference to the accompanyingdrawings, in which like reference characters refer to similar orcorresponding parts and in which:

Fig. 1 is a side view, partly in section, of a silencer in accordancewith the invention attached to a firearm;

Figs. 2 and 3 are cross-sectional views, to larger scale, of thesilencer of Fig. 1 taken along the lines '.-Z2 and 33, respectively;

Fig. 4 is a side view, partly in section, of a modified form of thesilencer of Fig. 1 in which the rear portion of the chamber is builtaround the barrel; and

Fig. 5 is a cross-sectional view, to larger scale, of the silencer ofFig, 4 taken along the line 55.

1 shows one form of the st l'ncer it at tached to the end of the barrelH of a firearm l2. The silencer it comprises a cylindrical chamberhaving a rear section 83 and a front section 2|, both containing heatabsorbing inaterial, through which the bullet passes with minimumclearance. The side walls of the rear section it are formed by the metaltube It which is securely fastened at the rear to the apertured endpiece It and at the front end is internally threaded to receive theapertured connector" ll. The heat absorbing material in the section i3is in the form of a number of annular discs 18 of metal screen stackedone upon another and held in compression by the connector ii. The" endpiece it includes as an integral part thereof an internally threadedcollar H) which screws onto the threaded muzzle of the barrel H to holdthe silencer l 0 securely in position.

The front section 2| comprises a metal tube 22 securely attached at itsrear to the connector lil', threaded at its front end to receive theannular end piece 23, and filled with annular discs 24 of metal screen.A forward sight 26 is provided at the front end of the silencer I0. Inorder to save drawing space parts of the sections I3 and 2| have beenremoved. Figs. 2 and 3 are crosssectional views.

The effectiveness of the silencer It depends upon its length andcross-sectional area. However, applicant has found that thecross-sectional area may be reduced at the front end of the silencerwithout a proportional reduction in its ability to silence the muzzleblast. This is due to the fact that the powder gases have already beenconsiderably lowered in temperature and pressure before they reach thefront portion of the silencer and so it takes a smaller crosssectionalarea to cool them a given additional amount. Therefore, in accordancewith the invention, the front section 2| has a smaller crosssectionalarea than the section it. Furthermore, the original efiiciency may berestored by a comparatively slight addition to the length of thesilencer It). There results, however, a considerable reduction in weightand volume. This reduces the cost of the silencer and, more importantly,improves the balance of the firearm.

Figs. 4 and 5 show a modified form of the silencer it} in which the rearsection 2'! is built around the barrel l i of the firearm i2. The sidewalls of the section 21 are formed by the metal tube 28 which is closedat the rear by an end piece 29 securely fastened to the barrel H and atits front end by an apertured and flanged metal disc 38. The section 2?is substantially filled with heat absorbing material in the form oflayers of metal screen 32 wrapped around the 3 barrel II. To permit thepowder gases to enter the section 21 there are provided a number ofholes 33 through the wall of the barrel l I. These may, for example, bedrilled and, as shown, are arranged in four rows spaced 90 degreesapart. The distance of the first hole 33 from the breach of the firearml2 largely determines the muzzle velocity of the bullet, assuming agiven weight of bullet and a given powder charge. It has been foundthat, in order to save weight, the outer diameter of the standard barrelmay be turned down somewhat without unduly weakening it.

As shown, the section 21 may be eccentrically mounted, with the largerpart under the barrel ll, so that it may be of larger diameter withoutinterfering with the line of sight.

The front section 34 comprises a metal tube 36 internally threaded atits rear to screw onto the threaded end of the barrel I I, internallythreaded at its front end to receive the annular end piece 23, andfilled with annular discs 24 of metal screen.

The screen is preferably plated with some metal such, for example, astin before the discs l8 and 24 are punched. It has been found that thiswill largely overcome the tendency of the discs to develop loose wireends which might accidentally come into contact with the bullet as itpasses through them and adversely affect the dispersion pattern. Theholes in the discs l8 and 24 are preferably made only large enough toinsure clearance for the bullet.

What is claimed is:

1. A silencer for firearms comprising a chamber and a plurality ofannular discs of metal screen positioned within said chambertransversely with respect to the longitudinal axis thereof, said discsbeing stacked one upon another under compression and substantiallyfilling said chamber except for a passageway therethrough providing onlyminimum clearance for a'bullet.

2. A silencer in accordance with claim 1 in which said discs are platedwith tin.

WARREN P. MASON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 227,341 Zellner May 4, 18801,000,702 Thurler Aug. 15, 1911 1,127,250 Humm Feb. 2, 1915 1,173,687Thompson Feb. 29, 1916 1,229,675 Thompson June 12, 1917 1,331,474 MasterFeb. 17, 1920 1,482,805 Maxim Feb. 5, 1924 1,497,553 Dickman June 10,1924 1,687,308 Paradise Oct. 9, 1928 1,838,645 Voigt Dec. 29, 19312,043,731 Bourne June 9, 1936 FOREIGN PATENTS Number Country Date665,167 Germany Sept. 22, 1938

